The present invention generally relates to a fluid transfer device and, in at least one embodiment, relates to a fluid transfer device for transferring fluid from a sealed container such as a vial to a sealed fluid delivery device such as an ambulatory drug delivery device.
A wide range of injectable drug delivery devices are known in which a fluid medicament, such as insulin, is stored in an expandable-contractible reservoir. In such devices, the fluid is delivered to the patient from the reservoir by forcing the reservoir to contract. The term “injectable” is meant to encompass subcutaneous, intradermal, intravenous and intramuscular delivery.
Such devices can be filled by the manufacturer of the fluid delivery device or such devices can be filled by a pharmacist, a physician or a patient prior to use. If filled by the manufacturer, it may be difficult to provide the required drug stability in the device since the fluid may be stored from several weeks to a number of years and the fluid delivery device manufacturer must then be responsible for providing the required fluid. If filled by someone downstream, it is difficult for such a person to ensure that the fluid has completely filled the reservoir, i.e. that the reservoir and fluid path do not contain any undesirable air bubbles. In general, this requires priming the device by filling it in a certain orientation which ensures that the air is pushed ahead of the fluid, such as with the filling inlet at the bottom and the delivery outlet at the top (to allow the air to be displaced during filling). Also, transferring fluid from one container to another typically results in at least some wasted fluid.
It would therefore be desirable to provide an improved fluid transfer device for safely and efficiently transferring fluid between two containers.